The invention relates generally to aircraft flight data analysis systems. More particularly, the invention relates to aircraft data analysis systems that make user-defined measurements on a set of flight data obtained from a variety of sources and post-flight measurement and trending analysis software that provide a user configurable measurement system for analyzing flight data from a variety of sources.
Data recorders on board modem aircraft record information about hundreds or thousands of operational parameters, such as ground speed, pitch and altitude at a rate of multiple times per second. The information thus collected is of great value to persons concerned with safety, aircraft maintenance, crew training, and other aspects of aircraft operation. However, the amount of information recorded during a single flight exceeds the analytical ability of even a skilled analyst. The amount of information collected from all the aircraft in a commercial fleet over a period of several months is staggering. Computer-assisted methods of analyzing flight data have been developed by airlines, government entities responsible for flight safety, and by others responsible for some aspect of aircraft operation. These computer assisted methods have to attempted to analyze the data for a number of purposes, including reducing accident rates and producing cost savings.
Traditional analysis has focused on sequentially searching recorded data from a single flight for an event or events of interest. An event is defined essentially as an out of tolerance instance where the value of one or more parameters exceeds acceptable limits as defined by safety considerations or the standard operating procedures of the aircraft operator. Existing flight data analysis systems operate by sequentially searching recorded data for a single flight for an event or events of interest and only generate a report (also called a "log") if such an event occurred. However, it is often useful to know the normal range of a specific parameter over many flights, independently of whether or not an event has occurred. Information about normal ranges of a given value over many flights, where the normal range of the value is a function of actual operations rather than a specified number or limit, is not easily accessible using given methods of flight data analysis. It is also often useful to know the normal range of a specific parameter during multiple flights of a number of airplanes of the same type of aircraft also called a "fleet"). For example, it may be useful to know the average aircraft speed during selected time points during takeoff for multiple flights of a particular aircraft or for a particular type of aircraft. It may also be useful to know that same information for other aircraft within the same fleet. These and other types of analyses are not provided for in existing flight data analysis systems.
In addition, existing flight data analysis systems are not easily configured by users and instead often require software changes to be implemented by the software manufacturer whenever a user wants to perform a measurement not currently provided for in the software data analysis program. The user is generally not allowed to configure the needed measurement just prior to or at the time of the time of flight data analysis. This severely limits the capability of existing flight data analysis systems to evolve as the flight data analysis needs and parameters change.
Also, in existing flight data analysis systems, the analysis is specified separately for each fleet (aircraft type). This makes it difficult to compare the analysis results between different fleets (aircraft types). Additionally, the work of setting up the system must be repeated for each fleet (aircraft type).